RESUMO
BACKGROUND AIMS: Ex vivo production of red blood cells (RBCs) represents a promising alternative for transfusion medicine. Several strategies have been described to generate erythroid cell lines from different sources, including embryonic, induced pluripotent, and hematopoietic stem cells. All these approaches have in common that they require elaborate differentiation cultures whereas the yield of enucleated RBCs is inefficient. METHODS: We generated a human immortalized adult erythroid progenitor cell line derived from bone marrow CD71-positive erythroid progenitor cells (immortalized bone marrow erythroid progenitor adult, or imBMEP-A) by an inducible expression system, to shorten differentiation culture necessary for terminal erythroid differentiation. It is the first erythroid cell line that is generated from direct reticulocyte progenitors and demonstrates robust hemoglobin production in the immortalized state. RESULTS: Morphologic analysis of the immortalized cells showed that the preferred cell type of the imBMEP-A line corresponds to hemoglobin-producing basophilic erythroblasts. In addition, we were able to generate a stable cell line from a single cell clone with the triple knockout of RhAG, RhDCE and KELL. After removal of doxycycline, part of the cells differentiated into normoblasts and reticulocytes within 5-7 days. CONCLUSIONS: Our results demonstrate that the imBMEP-A cell line can serve as a stable and straightforward modifiable platform for RBC engineering in the future.
Assuntos
Antígenos CD , Diferenciação Celular , Células Precursoras Eritroides , Receptores da Transferrina , Humanos , Células Precursoras Eritroides/citologia , Células Precursoras Eritroides/metabolismo , Receptores da Transferrina/metabolismo , Antígenos CD/metabolismo , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Eritropoese , Linhagem Celular , Eritrócitos/citologia , Eritrócitos/metabolismo , Reticulócitos/citologia , Reticulócitos/metabolismoRESUMO
The high variability of the human leukocyte antigen (HLA) remains a major obstacle to the application of allogeneic products in cell-based therapies. We have developed a strategy to decrease the immunogenicity of cell and tissues to improve their survival after allogeneic transplantation in the absence of immunosuppression. Using RNA interference technology, the expression of HLA class I and II was stably downregulated. HLA-silenced cells demonstrated to prevent a de novo and escape a pre-formed alloimmune response in vitro and in vivo. Also, they demonstrated to be capable of engraft and survive after allogeneic transplantation independently of the donor's and recipient's genetic background. The generation of HLA-universal cells has may open new horizons in the field of regenerative medicine. Some of the potential clinical applications of HLA universal cells will be discussed in this review.